Abstract: A ball hitch coupler which provides a simplified structure for coupling a ball hitch mounted on a towing vehicle to a coupler mounted on a trailer. This invention provides an innovative single cam pin locking mechanism, which in combination with a safety pin device and a tension spring provides a strong and secure ball coupler which has a minimum of moving parts and is designed to be easily used by a user by hand.

Abstract: An improved fifth-wheel extension adapter is described whose design provides the adaptability necessary for mating of the extension adapter with all known trailer king pin designs, which further provides improved contact with the trailer king pin and which provides structure for visually observing the relative position of the extension adapter and the hitch assembly located in the bed of the towing vehicle. The fifth-wheel extension adapter comprises a vertical column, a bottom portion designed to releasably connect to the hitch assembly and a top portion designed to adjustably mate to a wide range of trailer king pin designs. The fifth-wheel extension adapter is further designed to be easily attachable and easily removable permitting the operator maximum flexible use of the towing vehicle as well as the ability, with only one extension adapter to tow the widest variety of fifth-wheel trailers.